Electric potential and movement of charges If electric field is not present does that mean that charges achieve condition of electrostatics I.e, charges are stationary ?
But we say that stationary charge can produce electric field. 
I read this statement one a page (link given below)
 "Now if there's any $\vec E$  inside the conductor , we can surely say then the charges must move ." 
link: Charge inside conductor
 A: If there is an electric field, then there will be a force on a charged particle since $\vec{F} = q \vec{E}$. If you put a single charged particle in perfect vacuum, then if you add another charged particle then both particles must either move away from or towards one another, depending on whether the charges of the two particles have the same or opposite sign.
Now, in the case of a conductor, the electrons cannot leave the surface of the conductor. The surface acts as a barrier, since otherwise all of the electrons would simply leave the material. Since all of the electrons want to move away from all of the other electrons, the electrons will end up distributed on the surface of the conductor. Once this happens, an equilibrium is established where the electric force is balanced by the potential barrier at the surface of the conductor (this is somewhat analogous to the normal force of a surface balancing the gravitational force, which is why you don't fall through the floor).
Now, once all of the electrons arrange themselves in such a way as to establish an equilibrium, it turns out that by superposition the net electric field inside the conductor vanishes. This is evidenced by the fact that none of the electrons move (no force implies no electric field). Thus while each electron produces an electric field, the net electric field is zero inside the conductor.
